The Office of Precious Minerals (OPM) is the arm of the Ministry of Lands, Mines and Energy which regulates the marketing of precious minerals within the Republic of Liberia. OPM serves as the official conduit for all precious mineral exports out of Liberia. OPM conducts valuation on precious minerals (Gold and Diamond) to determine export values and associated royalties payable to Government Revenue. Due to parallel economic impact of the gold and diamond sectors, the Gold and Diamond Appraisal Offices, which operated separately in previous times, were amalgamated in 2004 to establish the Office of Precious Minerals. This department falls under the supervision of a manager whose functions and authority equals that of an Assistant Minister.
During 2013, the Government Diamond Office processed 84 (eighty-four) KP certificates for the export of rough diamonds with no record of imports into Liberia. Total volume of rough diamonds exported for 2013 was 43,805.05carats with estimated value of US$14,865,502.85 (Fourteen million, eight hundred sixty-five thousand, five hundred and two dollars 85/100); the accrued royalty paid to Government revenue was approximately US$445,965.09 (Four hundred forty-five thousand, nine hundred sixty-five dollars, 09/100).